USB to I2S with CMA6631A - the problems of sample rate conversion

Hi everybody,

i'm in the middle of designing a cheap and easily diy-able USB to I2S converter.

I already designed and assembled a PCB and it works (still has some minor design flaws), the computer is able to recognize the device, it downloads the ASIO drivers from Windows Update automatically, and i can use foobar2000 to have bit-perfect data coming out at the end of the optoisolator.

There is one question however that doesn't let me sleep:
should i upload a framework to the device that only allows 384kHz/24bit (sadly no 768kHz on the CM6631A) and throw out foobar2000, and use the built-in sample conversion in Windows (or macOS or Linux, i presume this would work with the 3 big operating systems) and basically force every OS to use software conversion, allowing me to skip using a hardware-based SRC

or

should i go wild, have every sample rate and bit rate supported, but use an SRC that always converts to 768kHz/24bit so that the analog filter doesn't have to be too sharp in order to properly filter the harmonics?

At the end of the interface i want to use the PCM1704, that's why i choose the sample rates.
 

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